Nearly everyone who bends over the crib of a baby bursts into bubbling, musical tones to try to get the infant's attention. This baby talk, or “motherese,” is widely considered to be a universal feature of human language, but now scientists report that a similar phenomenon might exist in other species—a finding that could help explain baby talk's evolution.

Rhesus monkeys use special vocalizations called grunts and girneys when they are around infants, but most researchers had believed the monkeys were directing the sounds at the mothers holding the babies. Now University of Chicago biologists Dario Maestripieri and Jessica Whitham have shown in a careful observational study that the monkeys were aiming the soft, nasal sounds at the infants. The vocalizations, Maestripieri says, are probably intended to get the newborn's attention and facilitate social interactions among group members—some of the same functions baby talk is thought to serve in people.